The name of the author is the first to go followed obediently by the title, the plot, the heartbreaking conclusion, the entire novel which suddenly becomes one you have never read, never even heard of,

as if, one by one, the memories you used to harbor decided to retire to the southern hemisphere of the brain, to a little fishing village where there are no phones.

As a poet Billy Collins is incomparable. But his “Forgetfulness” is not describing typical Alzheimer’s Disease. He is describing the common age-related slowdown in speed of recall, and the (extremely frustrating) loss of individual names, identifiers or even words. This is not dementia.

Of course, the poet does not claim it is dementia. The title is “Forgetfulness,” after all — and that is exactly what he describes. It is the popular psyche, if you will, that conflates forgetfulness with early dementia. They are different.

As a favorite resource tells us, there is a quantitative difference between forgetfulness and dementia. A person with normal age-related memory changes might forget a part of an experience; the person with Alzheimer’s Disease may forget the entire experience. While you might later remember what you forgot, the person with dementia is unlikely to recover the memory later. Do you leave a blizzard of notes to help you remember things? The demented patient is likely unable to use note-taking to assist with memory.

How can you tell if you are experiencing “normal” (whatever that means) forgetfulness as a part of the aging process, or demonstrating early symptoms of dementia? One reassuring rule of thumb: if you’re asking the question, it indicates the former is more likely. Dementia often interferes with both memory and reasoning, and your inquiry suggests that you are thinking through the possibilities and ramifications.

What if you are trying to get a sense about a family member or friend? Here are some indicators that memory problems might be early dementia:

Misplacing keys or other items might be normal aging. Putting them in the refrigerator, or in an unlikely hiding place, might indicate the possibility of dementia.

Putting on too many (or too few) clothes for the season — particularly if clothes are layered inappropriately — might suggest a problem.

Forgetting an appointment is not uncommon. Showing up a week early, or at the wrong place, is more problematic.

Inability to “get” sarcasm is a common problem in early dementia. Some people don’t like sarcasm in others — but that’s not what we’re talking about here. Demented people may also miss cues that someone they are talking with might be lying.

Falls are several times more likely among those with dementia. A recent history of increasing falls might raise the possibility of early dementia.